CORE C: LIPOPROTEIN CORE LABORATORY It is the objective of this laboratory to provide plasma lipoproteins and purified apolipoproteins isolated according to carefully standardized procedures for use by the individual projects within the program. This core facility is central to the Program Project and every member utilizes it. This core has four main purposes which are: I. Lipoprotein Production a) Large-scale isolation and purification of lipoproteins and related products from normolipidemic human serum by ultracentrifugation b) Isolation and purification of lipoproteins from mouse sera by ultracentrifugation c) Analytical preparation of lipoproteins from experimental samples (including mouse sera, dyslipidemic human sera, and tissue culture media) by FPLC II. Apolipoprotein Production Isolation of human HDL apolipoproteins apo A-l and A-ll Characterization of Lipoprotein and Apolipoproteins Using the Following Techniques: a) Agarose gel electrophoresis of lipoproteins b) SDS-PAGE of apolipoproteins c) Immunoblotting of apolipoproteins d) Separation of a-HDL and pre-(3-HDL particles by 2D-native gradient gel electrophoresis e) Electron microscopy of native and reconstituted lipid-protein complexes IV. lodination of Lipoproteins Labeling lipoproteins with 125l-tyramine cellobiose for determining sites of apoprotein degradation in vivo. The benefits arising from the centralized service provided by the Core Laboratory include: 1) uniformity of materials and techniques; 2) optimal use of space, supplies and equipment, especially centrifuges and FPLC.